How many mythical creatures can you have before they start to take away from the story?
This is another case of there being too many variables to be able to give you a set number. Longer works can incorporate more than shorter works, and give them more description. Shorter works can give each minimal description, but still technically have more, just as minor details rather than epic staring creatures. Your ability to portray them and portray them as different creatures is another factor. If you mean as main characters, then it depends on how many characters you and your readers will be able to handle, how many you have to have, how focused you want to get for any one, a lot of things.
We can't really give you an answer. I'm not even sure if you mean how many creatures in the form of details, minor characters, major characters, scene, or anything else, like a myth.
But isn't that the meaning of life?
Firebadger
That's Monty Python!
I was referring to Douglas Adams, and that was not the question, now was it?
ahem, just to be clear.
42 was the ANSWER to the question of the meaning of life, the universe and everything. Of course they didn't know the question. The Meaning of Life( Monty Python, the machine that goes PING!) is a separate subject.
and not coincidently, 42 is the reason I bought my house
ETA: alcohol may have influenced this post.
Okay so let me get this strait, the mythical creature count for a novel can be:
~stuffed if you happen to be Jim Butcher.
~It doesn't really matter, your MC probably won't know them all anyways.
~Less than 42.
~Around three before your audience not only had to pay for the book, but for a hole in their wall.
~Depends on the length of the story.
~Whatever as long as they have some point.
~Fewer than needed for an appendix/ reverse look up table.
~As long as they aren't mutilated earth animals you're fine.
~3 (including a loin-horse, a Manticore, and a Firebadger)
~Just look at them as another character you creature-ist!
~You have to keep them in line, once they step out of the garden they are gone!
~As long as they don't have bizarre names they can stay.
~As many as it takes.
~Drinking helps fluid writing.
I think the favorite though is 'As long as they don't take from the story'. Am I correct?